Transmission



Oct. 21, 1930. c. COTTAETAL v 1,778,970

TRANSMISSION Filed May 2'7. 1927 2 Sheets-Sheet 1 ,12 5 I 30 34 17 f% z Oct. 21, 1930.

c. COTTA ET AL TRANSMISSION 2 Sheets-sheaf. 2

Filed May 27, 1927 Patented Oct, 21, 193i) oniantnseo'rrn AND CHRISTIAN R. MiaRTHlililljS, p11?JRIDQELEOB-DliIlIiLIltltlliS, refe ences TO sarncnannnseooriia j I TRANSMISSION zA pplicati o nfiled May 27,

This invention relates to power. transmis: sions, and is more particularly devoted to transmissions designed for use in connection with marine engines or'wherever it is -de-' sired to provide a forward and reverse drive without involving a complicated and in]: practical form of transmission mechanism or one whieh is.-'apt is become noisy; or; get 7 outof order. -T p r The principalfobject of the presentjnvention is to provide a transmission of the type referred to, Controlled by a singlelever which when'shifted in one direction from a neutral position secures a forward drive and when shifted; in the other direction secures;..a-,re-,

verse drive, thusyadaptingfthe sameit0 the requirements of 1 marine installations. Y .The

transmission comprises an ordinary one-way clutch which simply completes the driving connection between the driving. and driven shafts, and an ordinary two-way clutch. which determines the direction ofdrive: so 7 as to drive the 'drivenmember selectively in either direction, the two clutches being controlled jointly by a novel. and highly practical form of means for'completing the, drive in two directions ,under-the controlof'the i aforesaid lever, and the clutchesloein en'- gaged in a predetermined relation. tolone an other so that the two-way clutch,"whicl1 is preferably ofthe jawtype, is insured of proper engagement upon each engagement of the one-way clutch, which may be1ofiany;or dinary frictiOntype;

The invention is illustratedin the accom= 'panyingdrawings, whereinFi'g. 1 is a vertical section through the transmission clearly showing the two clutches with thefirst or two-way clutch" disengaged, this "being the relationship of the p artsiwithtthe controllever in theneutral mid-position;

Fig. 2 is a horizontal section througha portion of Fig. 1 to show the shifting mechanism in plan r p Fig.3is a side view of the shifting cams on an' e nlarged scale, the same appearing as they would if viewed on the line 3+3 of Fig. 2, except for the intervening wall of the noted is of the jawltype, will properly e11 gage in either of its positions wlththe clutch 6, constitutesthesubject matter ofsthe pres- 1927. Serial no: 1 4,57 3

transmission casingap'pearing in that figure,"

which is omitted;;,and-- I v Fig lisa view corresp nding t -FigVB of a; modified or alternative constructiom The same or similar reference numeralsar'e' applied to corresponding parts throughout the views. v p

5 The,presentxinvention(is, of;course,,a,r plicableto practically'any' type of internal combustion engine and for that reason only the end of vthe crankshaft of the engine is1- illustrated at 5; F or, the present purposes I this may be ,regardedgas the driveshaftjon drive element. The one-way clutch 6 is ar ranged to provide a driving connection-be;

tween the shaft 5andanintermedi'ate driven shaft? at thevfiy; wheel 8 as in the case of an vention is .not to be considered as limitedto such an arrangementinasmuch as inmany automobile transmission, However, the inthe driven isha'ft.- I A two-wayclutch; 12" is arrangedtotransmit the drive from the in termediateshaft 7 in either direction; to the driven shaft 10. Thus,briefly stated, when the two-way clutch 1' 12 is in one of its engaged positions and the clutch 6 .is also 'en-.

gaged, the" drive will be transmitted from the shaft 5 to the shaft lO inone direction,

the reversal in direction of drivebeinglseg cu'red-by the shifting of the; two-way clutch 12 to its other engaged position. -Themeans forj jointly controlling the 1 two fclutches so, that the 1 two-way clutch 12, which it. will be ent invention and is described'inidetail'here j ina'fter; The-intermediate shaft 711s receivedin front and rear bearings 13and 14 provided in the fly wheel 8 and in a front wall of the f gear box 9irespectively; Thecclutch 6.is of I the pushty pe and the disc 15thereof, which is splinedas at 16 on the shaft 7 ispres'sed against the flywheel by the pressurevplate {10s I 17 under the action of levers 18 pivotally' mounted on the back plate .19 and'normally urged to their engaged position by the collar, 20'u'nder the action of the compression spring 21.. The latter, it will be noted,'is

'f'roni' the levers 18' and hencei releases' the.

7 pressure on the plate 17 to release the clutch.

A'rock'shaft 221mm. yoke 23 fixed thereon arranged in the rocking motion of the shaft to'engage or disengage the'clutch by actu ation of the collar 20, No invention is claimed in the particular details *of' the VT clutch as justdescribed, except only in so far as the same contribute; toward the combina tions and arrangements herein claimed to be new, Rocking -motion isarrange'd tobe transmitted to the shaft 22 for the engage ment and disengagement ofthe clutch; 6 by a reciprocable shifter rod 24-operable in bearings at25 and-26on the side wall of the gearbox 9 and pivotallyconnected as at 27 to an 28"fixed on th'e end of the shaft'22. 7 Thedriven shaft V ward end in a bearing 29-within a gear 30 provided on-the rearward end of the intermediate shaft 7 .l The clutch 12" comprises a collar 31 splined on the shaft 10andprovided with clutch teeth 32 and 33 at its opposite ends. The teeth 32 are arranged to intermes'h with teeth 34 provided on the rear face of the gear 30 whereby'to transinit'the drive directly from the intermediate shaft 7' to'the driven shaft 10. Tl1eiteeth 33 on the other hand are arranged to intermesh withteeth 35 provided on the forward face ofa gear 36 mounted freely on the shaft 10.

The gear 36 is arranged to be driven from the intermediate shaft 7 but in the reverse direction to the gear 30 through the gear:

train 30%37, 38 .39 and 391-36. The gear 39 isa reverse'idl'er gear and is indicated in dotted lines because it occurs in front of the plane of section. Obviously then, when the collar 31'is shiftedrto the right ;inFig. 1, the shaft 10 will be driven in thereverse di rection to the shaft 7; The particular details whereby the two-way driveis secured at the clutch 12 also forms nov part of the presentinvention, except'only in so far-as they contr bute toward the arrangements and combinatlon's herein claimed to be new.

The collar 31' is annularly grooved as at 40 to receive the shifteryoke or fork 41 mount-- edon the shaft 42 received in bearings as at 43 in the front and rear walls of the gear According-to the present invention, the clutches 6 and 12 are jointly controlled by a'single lever 44 which is either operated 1; directly by the pilot who grasps the handle end thereof, or is operated through interrmediate linkagefrom the pilots cabin. The

lever 44 is fixed to a rock shaft 45 and is arranged through the medium of the operat- 7 ing connections, which will now be described, 'to operate 'the shiftingrod 24 and yoke 41 to engage theclutches 6 and 12for forward drive wh'enthe lever is swung forwardly: from the neutral mid position, in whichthe pins am 51 respectively. to provideoperating connections with the rod '24 and yoke 41; The two slots deviate from the dotand dash arc XY, which is taken as a normal in Fig. 3,

to the extents illustrated, the deviation one way or another causing thelineal movement of the rod or yoke correspondinglyone way or another in the rocking of thecams'with the shaft 45 in a'manner'fbelieved to be selfevident. Assumeforlthemoment that the y 'control' lever 44 is thrown forwardly, that is, 10 is received atfits' for} is moved in a counter-clockwise direction as VlWBQtlIl Flgs. l'-and 3;"the"two cams are,

of course, correspondinglyshifted. The pin 50, due .to the outwardlyfolfset "portion 48 of the slot 48,'is moved to thefleftfromthe position illustrated and at the limit of the movement of the cam is moved back again to its first position. The pin 51 'on'the-oth'er hand, is moved tothe left due to the outwardly offsetpart 49 of the slot ,49 and at the limit of the movement of the cam remains displaced to the left relative to the normal position shown, Applying this information to a reading ofFigs'. 1 and 2, it will thus be evident that the shiftingrod 24 for the clutch 6 is moved to the left and back again, whereangular relationship ofithe offset portions 48 and 4990f the slots 48 and 49 by reference to the dotted radial lines in Fig. 3) the clutch 12 is shifted to engage'theteeth- 32 with the teeth 34, andimmediatelythereafter the clutch 6 is reengaged. "Inother words, the operation of the cams 46 and 47 by tthe lever 44 results in such-timed operation 'ofthe rod 24 and yoke 41 that the engagement of the jaw clutch is'po'sitivelyinsured and the engagement of the friction clutch does not.

occur until the engagement of the jaw clutch is completed. The aw clutchfis rendered certain of engagement because the friction clutch is disengaged andengaged for each engagement of the jaw clutch and likewise for each disengagement thereof, thus insuring thatthegears 30 and 36 will be in motion whenever"rtg sidesired' to engage-' the aw I clutch;-there is never apt to be 'a situation where i the teeth "32%34 or- 33 85 will not mesh such as would otherwise be the case.-

It is hardly necessary to trace' out inasmuch detail the operation restilting "when i the lever 44 is thrown to'the rear for the reversedrive sinceit is evident upon observation of the cam'slojts- 48 and 49 in Fig. 3 that the only difierenc'e inthisoperation isthat the pin 51 is'shifted totlie right from the normal or neutral position illustrated whereby toengage the clutch teeth 38 with the teeth 35. This is due to the fact that the slot 49 is oflfset inwardly as at 49 atthe lower end of the slot. The'slot 48 has an outward oifset 48 correspondingin form tothe offset/48 provided onlthe upper end of the slot 48. The angular relationship of the offset por tions of the two slots, as in the other case just described, is such as to insure the engage -ment of the jaw clutch 12 before the engagement of the friction clutch 6 is completed or, as. a matter of fact, is commenced, Here, again, the fact that the gears are in motion when the jaw clutch is being engaged, be cause the friction clutchis engaged after dis-f engagement of the. jaw clutch, as previously described, makes it a matter of almost absolute. certainty that the jaw clutch will engage properly. I

In the modified or alternative form illustrated in Fig. 4,v the cams 46" and 47 have "the slots 48' and 49 thereof conformedapproximately as in the'cams shown in Fig. 3,

the principal noteworthy exception being that the middle portion of the slot 48 is not offset relative to the normal arc XY as in the form previously described. In other words, in the present form boththe clutch 6 and the clutch 12 are disengaged when the control lever 44 is in the neutral mid-position. The clutch '6,

due to the form of the cam slot 48, remains A disengaged until the lever arrives near either of the limit positions for forward and reverse drive. The cam 46, it will be noted, is fixed to rock with theshaftso that it is positively operated with the lever 44, whereas'the cam 47. is mounted freely on the rock shaft 45 and is arranged to be moved yield- I ingly in either directionby the lever 44-, there bemg compression springs 52 acting between the opposite sides of the cam and fingers 53' formed integral with the lever 44 and projecting in spaced relation to the sides of the f under compression tending to shift the clutch 1210f the left. If,h'owever, the teeth 32 should not chance to mesh with the teeth 34,

the .c1utch'f12 will not engage for an instant c until the gear 30'com1nences' to turndue to the e engagement of the-clutch 6. Iii-other words;

the'othertype' ofcontrol permits of positive shifting of-the two clutches J-by reason'of' the; fact that the gears 30 and 36 are turning rein}:

tive to the sleeve 31 atthe' time that the clutch 12 ispshifted fthus insuring. the engagement either of the teeth 32 and s34 or'the'fteethi83- and35, asthe casemay be: In the present:

case,h o.wever, where'thepartsare caused to beengaged from a standstill, if the partsdonot happen to "be positioned-so that the teeth I willmesh, this meshing will occur'practically sd-I immediately upon the engagement of theft-ic tion'fclut'ch. f"

f Itus; believed v conveys a clear understanding of our nvenfdre oiiig description v i tion and of itsiv'arious obj ectsland advantages. VVhIle' the'same "has been illustrated in tWOi j specific forms, it will be obvious that itis v capable of embodimentin still other forms.r 5 For that reasonthe'appen'ded claims have-- been, drawnflwith a View toycovering-otherlegitimate in'odificationsand adzq' tations;oo n-=v sidered as coniin-gwithin thespiritands'cope 7 2 of the invention. W nn 1.,Ina power tiono'f afhousinghavin'ga dri-vingshaft and positeends thereof, an intermediate: shaft in said housing, afriction clutch for connectingthedrivingshaft with theintermediate shaft, a aw clutchshiftable in either direction to connectthe intermediate shaftwith the driven shaft for either forward or reverse drivel a' shifter rod having connection with said friction-clutch and shiftable back and forth for 3 disengaging and engaging'the same, .a shifter yoke .havingconnection with the jaw clutch and shiftable in either direction toengage'the latter foreither forward or'reversedrive', the

shifterrod andishifterl yoke being movable in parallel directions, a rock shaft bearingin sa d housing, means outside the housing for communicating rockmg motion to said shaft,

and a pairof camsectorsmounted onv said shaft ,to rock ther ewith,both ofsaidsectorsv I havlng cam shaped slots receiving'pins' pro a driven shaft extending into and out-of-op-i;

vided respectively on :theshifter rod and shifter yoke and being so conformed that in I the rockinggof said shaft in one direction the shifters both move *inzonedirection to engage the clutches for driving in a certain direction and whenrocked 1n the other direction the two shifters are moved in difierent directions to engage the clutches for driving in the opposite direction.

2. In: apower transmission, the combination with a drivingshaft anda driven shaft,

ofan intermediate shaft, afriction clutchfor.

connecting the, driving shaft'withthe intertransm ssiomthe'comb n 1 and shifter yoke-being movable in parallel directions, arock shaft supported in trans- 1 verse relation to the shifter rod, means for communicating rocking motion to said shaft,

and a pair of cam sectors interconnected for oscillation together, at least one of said cam direction to engage, the clutches for'oneidrive and when rocked in the otherfldirecjtion the two shifters are moved inopposite directions to engage the clutches for, the other drive.

In lwit-nesswhereof "we have hereunto affixed our signatures. V V

1 "CHARLESQOTTAJ M J i CHRISTIAN R." q 7 I in sectors "being mounted on the rock-shaftfto beoscillated thereby, both of saidsectorshaving cam-shaped slots receiving pins provided respectively onfthe shifter rod and shifter n yoke and being so conformed that in the rock-" 3 ing of said 'shaft in one direction the two 1 shiftersfmove n one direction to engage the clutches for drivlng in a certalni direction and when rocked inthe other direction the two I f shifters are moved inopposite directions to engage the clutches for driving in the 'OPPOE, a

site direction.

3. In a power transmissiom'the combina tion of a driving shaft, a drivenshaftjand an 'i'ntermediateshaft disposed inparallel rela} r tionto one another, a housing for said shafts,

a friction clutch for connecting the driving shaft'withthe intermediate shaft, these, two 1 shaftsbeing coaxial, jawfclutching means shiftable in opposite directions to connect the intermediate shaft; with the driven'shaft for two different drives, a shifter rod and a guide roddisposed in parallel relation to one an, other and received in bearingsin the housing walls,the shifter rod being reciprocabletshifting means operated by the shifter rod for disengaging and engaging the friction clutch, a shifter yoke mounted on the guide rod for re ciprocation and connected with the jaw clutching means to engage, the same for one i'io drive when moved to one position and for the other drive when moved to the other posi- 7 tion, a'rock shaft disposedin transverse re lation to theshifter rod and guide rod in a hearing, in said housing, means outside the housing for communicating rocking motion to" said shaft, and a pair of cam sectors interconnected for oscillation together, at" least one of said sectors being mounted on the rock shaft for oscillation thereby, both of'said sectors having cam-shaped slots and the" one H sector being directly connected with the end of the shifter rod by receiving'a pin on said rod in the slot therein and the, other sector having direct operating connection with the shifter yoke byreceiving a pin on the yoke in the slot therein, the said cam slots being so conformed that in the rocking of said shaft in'one direction the two shifters move in one 

